Sanofi Launches Phase III Clinical Trial of Intranasal RSV Vaccine for Infants

▎Armstrong

On November 27, 2024, Sanofi registered a Phase III clinical trial for its RSV vaccine for infants and young children on the Clinicaltrials.gov website.

This Phase III clinical trial plans to enroll 947 infant subjects aged 6-22 months, with an expected completion date of April 2026.In February this year, Sanofi has already launched the phase III clinical trial of the vaccine with 6,300 cases. This phase III clinical trial is exploring...SameImmunogenicity and safety of the dose.

Although GSK and Pfizer's RSV protein vaccines have been approved for marketing, and Moderna's RSV mRNA vaccine Phase III clinical trial has also succeeded, Sanofi chose a differentiated strategy. Sanofi’s RSV neutralizing antibody had a strong debut with $700 million in sales in its first year on the market in 2023, mainly used for newborns, and its RSV spray vaccine also targets infants. SP0125 is a live attenuated vaccine administered via nasal spray.

For newborns, the first step is to register for Beyfortus to protect against infections during the first epidemic season, followed by two doses of the nasal spray vaccine between 4-9 months to ensure protection during the second epidemic season.

The nasal spray vaccine demonstrated a robust immune response in Phase 1/2 clinical trials.

Summary

Sanofi has implemented a differentiated strategy around RSV, with its RSV neutralizing antibody and intranasal RSV live attenuated vaccine providing protection for newborns during two epidemic seasons.Sanofi has also laid out plans for an RSV-MPV-PIV triple mRNA vaccine, a common strategy in the development of combination vaccines for respiratory viruses, with Pfizer/BioNTech, Moderna, and AstraZeneca/Isocovax also making similar moves.